'\" et
.TH POSIX_TRACE_EVENTTYPELIST_GETNEXT_ID "3P" 2017 "IEEE/The Open Group" "POSIX Programmer's Manual"
.\"
.SH PROLOG
This manual page is part of the POSIX Programmer's Manual.
The Linux implementation of this interface may differ (consult
the corresponding Linux manual page for details of Linux behavior),
or the interface may not be implemented on Linux.
.\"
.SH NAME
posix_trace_eventtypelist_getnext_id,
posix_trace_eventtypelist_rewind
\(em iterate over a mapping of trace event types
(\fBTRACING\fP)
.SH SYNOPSIS
.LP
.nf
#include <trace.h>
.P
int posix_trace_eventtypelist_getnext_id(trace_id_t \fItrid\fP,
    trace_event_id_t *restrict \fIevent\fP, int *restrict \fIunavailable\fP);
int posix_trace_eventtypelist_rewind(trace_id_t \fItrid\fP);
.fi
.SH DESCRIPTION
The first time
\fIposix_trace_eventtypelist_getnext_id\fR()
is called, the function shall return in the variable pointed to by
.IR event
the first trace event type identifier of the list of trace events of
the trace stream identified by the
.IR trid
argument. Successive calls to
\fIposix_trace_eventtypelist_getnext_id\fR()
return in the variable pointed to by
.IR event
the next trace event type identifier in that same list. Each time a
trace event type identifier is successfully written into the variable
pointed to by the
.IR event
argument, the variable pointed to by the
.IR unavailable
argument shall be set to zero. When no more trace event type
identifiers are available, and so none is returned, the variable
pointed to by the
.IR unavailable
argument shall be set to a value different from zero.
.P
The
\fIposix_trace_eventtypelist_rewind\fR()
function shall reset the next trace event type identifier to be read to
the first trace event type identifier from the list of trace events
used in the trace stream identified by
.IR trid .
.SH "RETURN VALUE"
Upon successful completion, these functions shall return a value of
zero. Otherwise, they shall return the corresponding error number.
.P
The
\fIposix_trace_eventtypelist_getnext_id\fR()
function stores the trace event type identifier value in the object
pointed to by
.IR event ,
if successful.
.SH ERRORS
These functions shall fail if:
.TP
.BR EINVAL
The
.IR trid
argument was not a valid trace stream identifier.
.LP
.IR "The following sections are informative."
.SH EXAMPLES
None.
.SH "APPLICATION USAGE"
None.
.SH RATIONALE
None.
.SH "FUTURE DIRECTIONS"
The
\fIposix_trace_eventtypelist_getnext_id\fR()
and
\fIposix_trace_eventtypelist_rewind\fR()
functions may be removed in a future version.
.SH "SEE ALSO"
.ad l
.IR "\fIposix_trace_event\fR\^(\|)",
.IR "\fIposix_trace_eventid_equal\fR\^(\|)",
.IR "\fIposix_trace_getnext_event\fR\^(\|)"
.ad b
.P
The Base Definitions volume of POSIX.1\(hy2017,
.IR "\fB<trace.h>\fP"
.\"
.SH COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1-2017, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 7, 2018 Edition,
Copyright (C) 2018 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group.
In the event of any discrepancy between this version and the original IEEE and
The Open Group Standard, the original IEEE and The Open Group Standard
is the referee document. The original Standard can be obtained online at
http://www.opengroup.org/unix/online.html .
.PP
Any typographical or formatting errors that appear
in this page are most likely
to have been introduced during the conversion of the source files to
man page format. To report such errors, see
https://www.kernel.org/doc/man-pages/reporting_bugs.html .
